Optical disc capable of revealing preservation condition

ABSTRACT

The present invention is to provide an optical disc which comprises a substrate and a multi-layer structure. The multi-layer structure is formed over the substrate, and at least one layer of the multi-layer structure contains an indicating material. Furthermore, the indicating material has a respective color changeable in response to permeation of oxygen or moisture into the layer containing the indicating material.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to an optical disc and, more particularly, to an optical disc which includes an indicating material.

2. Description of the Prior Art

The modern information revolution has led to an ever increasing demand for data storage systems. To this end, the extremely low cost per megabyte, mature technology, small size, and convenient handling of optical storage media, e.g., CD-R, CD-RW, DVD±R, DVD-RW, has resulted in the explosive growth of their use as a data storage and distribution medium. The user can easily apply these medium to store enormous amounts of movies, music, pictures or data.

However, because of the convenience of these optical storage media, users easily ignore the preservation environment of these media. Therefore, these optical storage media may be deteriorated by environment factors such as high humidity, increased temperature, light exposure and oxidation, and then be unreadable.

Obviously, it is important to warn the user about the preservation condition of the optical storage media, so as to prevent the damage of the stored data.

SUMMARY OF THE INVENTION

Accordingly, one aspect of the present invention is to provide an optical disc capable of revealing preservation condition thereof by an indicating material therein. In one preferred embodiment of the present invention, the optical disc includes a substrate and a multi-layer structure. The multi-layer structure is formed over the substrate, and at least one layer of the multi-layer structure contains an indicating material. Furthermore, the indicating material has a respective color changeable in response to permeation of oxygen or moisture into the layer containing the indicating material.

In another preferred embodiment of the present invention, the optical disc includes a first substrate, a multi-layer structure and a second substrate. Additionally, the multi-layer structure is formed over the first substrate, and at least one layer of the multi-layer structure containing an indicating material. The indicating material having a respective color changeable in response to permeation of an oxygen or a moisture into the layer containing the indicating material. Moreover, the second substrate is formed over the multi-layer structure.

The advantage and spirit of the invention may be understood by the following recitations together with the appended drawings.

BRIEF DESCRIPTION OF THE APPENDED DRAWINGS

FIG. 1 is a sectional view of an optical disc according to an embodiment of the present invention.

FIG. 2 is a sectional view of an optical disc according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of an optical disc in accordance with a practice of the invention.

FIG. 4 is a sectional view of an optical disc according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides an optical disc capable of revealing preservation condition thereof by an indicating material therein.

According to a preferred embodiment of the present invention, the optical disc includes a substrate and a multi-layer structure. In addition, the multi-layer structure is formed over the substrate, and at least one layer of it containing an indicating material. In particular, the indicating material has a respective color changeable in response to permeation of an oxygen or a moisture into the layer containing the indicating material. Please refer to FIG. 1, which shows a sectional view of an optical disc 1 according to the present invention. The optical disc 1 includes the substrate 11 and the multi-layer structure 13 as described above. Additionally, the multi-layer structure 13 further includes a recording layer 131, a reflecting layer 133 and a surface layer 135. Particularly, the surface layer 135 contains the indicating material 1351 capable of revealing the preservation condition of the optical disc 1.

In practice, the indicating material 1351 can be Cobaltous Oxide (CoO), Sodium diphenylaminesulfonate, ferroin or other material with the same character. In particular, the indicating material 1351 also can be a mixture of above materials.

Referring to FIG. 2, the optical disc 1 in accordance with another embodiment of the invention includes the substrate 11 and the multi-layer structure 13 as described above. Moreover, the multi-layer structure 13 also includes the recording layer 131, the reflecting layer 133 and the surface layer 135. In particular, in the embodiment, the recording layer 131 contains the indicating material 1311.

Similarly, the indicating material 1311 can be CoO, Sodium diphenylaminesulfonate, ferroin, other material with the same character or their mixtures.

In practice, the optical discs described above can be configured to comply with a CD-R specification or a CD-RW specification. In practice, the surface of the optical disc has at least one transparent area for observing the change of color of said indicating material. Furthermore, as shown in FIG. 3, the transparent area can locate within an extreme inner periphery 1131 or without an extreme outer periphery 1133 on the surface 113 of the optical disc 1. It should be noticed that the extreme inner periphery and extreme outer periphery of the optical disc means the extreme inner periphery and extreme outer periphery of the data recordable region respectively.

According to another preferred embodiment of the present invention, the optical disc includes a first substrate, a multi-layer structure and a second substrate. The multi-layer structure is formed over the first substrate, and at least one layer of the multi-layer structure containing an indicating material. Furthermore, the indicating material has a respective color changeable in response to permeation of an oxygen or a moisture into the layer containing the indicating material. In addition, the second substrate is formed over the multi-layer structure.

Referring to FIG. 4, the optical disc 3 according to one embodiment of the present invention includes a first substrate 31, a multi-layer structure 33 and a second substrate 35. Furthermore, the multi-layer structure 33 further includes a recording layer 331, a reflecting layer 333 and a bonding layer 335. In particular, in the embodiment, the bonding layer 335 contains the indicating material 3351.

In practice, the indicating material 3351 can be CoO, Sodium diphenylaminesulfonate, ferroin, other material with the same character or their mixtures. In practice, the optical discs described above can be configured to comply with a DVD-R, a DVD+R or a DVD-RW specification. In practice, the surface of the optical disc has at least one transparent area for observing the change of color of said indicating material. Furthermore, the transparent area can be located within an extreme inner periphery or without an extreme outer periphery of the optical disc.

Obviously, through the changeable color indicating material, the optical disc of the present invention is capable of indicating the preservation condition thereof. More important, users can easily observe the condition of the optical disc, so as to backup the data stored in the disc to ensure the safety of the data.

With the example and explanations above, the features and spirits of the invention will be hopefully well described. Those skilled in the art will readily observe that numerous modifications and alterations of the device may be made while retaining the teaching of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. 

1. An optical disc, comprising: a substrate; and a multi-layer structure formed over the substrate, at least one layer of the multi-layer structure containing an indicating material, and said indicating material having a respective color changeable in response to permeation of an oxygen or a moisture into the layer containing the indicating material.
 2. The optical disc of claim 1, wherein the indicating material is one selected from the group consisting of a Cobaltous Oxide (CoO), a Sodium diphenylaminesulfonate, a ferroin and their mixtures.
 3. The optical disc of claim 2, wherein the at least one layer containing the indicating material comprises a surface layer of the multi-layer structure.
 4. The optical disc of claim 2, wherein the at least one layer containing the indicating material comprises a recording layer of the multi-layer structure.
 5. The optical disc of claim 1, wherein the optical disc is configured to comply with a CD-R specification or a CD-RW specification.
 6. The optical disc of claim 5, wherein the surface of the optical disc has at least one transparent area for observing the change of color of said indicating material.
 7. The optical disc of claim 6, wherein the transparent area is located within an extreme inner periphery or without an extreme outer periphery of the optical disc.
 8. An optical disc, comprising: a first substrate; a multi-layer structure formed over the first substrate, at least one layer of the multi-layer structure containing an indicating material, and said indicating material having a respective color changeable in response to permeation of an oxygen or a moisture into the layer containing the indicating material; and a second substrate, formed over the multi-layer structure.
 9. The optical disc of claim 8, wherein the indicating material is one selected from the group consisting of a Cobaltous Oxide (CoO), a Sodium diphenylaminesulfonate, a ferroin and their mixtures.
 10. The optical disc of claim 9, wherein the at least one layer containing the indicating material comprises a bonding layer of the multi-layer structure.
 11. The optical disc of claim 9, wherein the at least one layer containing the indicating material comprises a recording layer of the multi-layer structure.
 12. The optical disc of claim 8, wherein the optical disc is configured to comply with a DVD-R specification or a DVD+R specification.
 13. The optical disc of claim 8, wherein the optical disc is configured to comply with a DVD-RW.
 14. The optical disc of claim 13, wherein the surface of the optical disc has at least one transparent area for observing the change of color of said indicating material.
 15. The optical disc of claim 14, wherein the transparent area is located within an extreme inner periphery or without an extreme outer periphery of the optical disc. 